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Solid Octagon

Solid Octagon leads the next generation of the Fly rod. Sou Maruyama is the founder of Solid Octagon. He has been running one of the most famous wedding band maker in Tokyo for years. But he could not stop his desire to be a fly rod maker, and he made it. Now he has two business holding in his arm, but he said " 95% of may brains is occupied with fly rod."

As its brand name tells, all Solid Octagon Models are made by solid graphite blocks.

Upper:8'3" #6 (30t carbon / Lower:7'6" #4(24t carbon)

Is lighter the better? Aren't you tired with the lightness & stiffness competition of the flyrods?

The history of the fly fishing rod has been an endeavor to overcome the heavy weight material. In Bamboo rod era, E. C. Powel invented the hollow construction of the Tonkin cane bamboo rod to make the rod lighter. It was not easy work to remove the core from each split pieces of Tonkin, but this innovative method was achieved by Winston. The next generation Glass fiber rod was born hollow, because the glass fiber sheet had to be rolled around the steel core(mandrel), and the graphite rod followed. The lightness of the graphite sheet made the graphite fly fishing rod lightest ever in fly fishing history.

Is lighter, better? We have to remember the weight is always an important factor with any tools. Could you imagine an ultralight hammer or featherweight scissors?

The flyrod should have the ideal weight for matching each line weight, rod length, but manufacturers seem to decide to ignore that most important factor. None of the major manufacturers has chosen to stop the lightest weight rod contest. We have to realize we come way too far. A small group of fly fishermen/fisherwomen have already noticed this and reverse the clock to get back to the right era. Apparently, bamboo and glass rod are their answer. I believe bamboo and glass are the still one of the best materials for the small streams such as many of the eastern rivers of the USA and the most of Japanese rivers. But we all know they are not the ideal rod for the Western rivers which often requires more than 8 foot for 5 weight. Most of the Bamboo rod of 8 foot 5 weight are too heavy to comfortably cast all day long.

We have so many bamboo rod builders who make functional and beautiful rods these days. It is a kind of strange to know the number of the bamboo rodbuilders are still increasing in this era of graphite rods. Experienced fishermen/fisherwomen are acquiring bamboo rods not only with their beautiful and authentic appearance, but also knowing they are exceptional fishing tools.

But we have to say it is still a big challenge for any bamboo rod builder to make over 5 weight rod in a longer than 8 foot length. That challenge mostly comes from Tonkin’s inherent weight. Many of the bamboo rod makers will agree if we say the max comfortable length of a Tonkin cane rod would be between 7’9” foot and 8’3”.

So, what’s the alternatives? Glass? Not a bad idea, but we still may feel uncomfortable with the weight when the rod length goes beyond 8 foot.

Then, how about a graphite rod? Is it still possible to add the weight on the graphite rod? That was the question we had when we started designing our own rod.

Graphite is still the excellent material for fly rod

We found that solid graphite stock was the answer. It was 9 years ago when we made the first prototype. If we have to say its action in one word, we would say “It’s not like a graphite rod”. It is also never like a glass rod, but rather close in feel to a bamboo rod. That feel comes from its solid construction.

Why solid?

Then why hollow? You have to realize the hollow construction is not required from the users. It came from the quest by manufacturers for light weight. Here is the common process to make a graphite rod blank.

1. Design a taper

2. Make a mandrel

3. Cut a graphite preimpregnated sheet

4. Roll the cut sheet around the mandrel

5. Heat that rolled graphite sheet with the mandrel core

6. Cool down after the heating

7. Pull out the mandrel core

8. Sand the graphite blank smooth

It is the most efficient method for mass production. Once you make up the mandrel, you just roll and bake the graphite. This process is also the best way to make a light rod, because the rod always comes out hollow. But once you need to add the weight, the process will be much more complicated. Because you will get the hollow construction as long as you use a mandrel.

We did away with this common method when we decided to add the weight to the graphite rod. Then we found the solid pultruded graphite cylinder. We believe it will be the ultimate material for the next generation of fly rods.

How to make tapered solid rod out of the cylinder?

As we decided to say good bye to the common method, we had to invent a way to machine the cylinder. So, we designed a machine just as Lyle Dickerson had made machines to enable him to make bamboo rods. We believe the real invention will start from the original method.

We named it “The Vertical Crawler (patented NO.2011-244770)“.

The Vertical crawler has a pair of mortise cutters, which are controlled by a computing system that can be set up in micro millimeter increments. As its name suggests, two cutters are crawl up and down the surface of the solid cylinder, which is held in a vertical position. The cutters are diamond coated and face each other to grind a graphite shaft two sides at a time. The cutter heads are rotated automatically as many times as required. Triangle rod, Quad rod, Penta rod, Hex rod, Hepta rod, Octa rod, and any polygonal shape rods including the usual round shape rod can be created with perfect precision.

The Vertical Crawler releases us from the inflexibility when we design the shape and taper of the rod. The Compound taper rod which is not uncommon in Bamboo Rod era, the flattened rod which we have never before seen, and even a combination shaped rod are not difficult to create.

Sou Maruyama is operating the Vertical Crawler

How does the solid rod work?

1. Heavier shaft generates slower acceleration

The solid rod reacts slower than hollow rod when it is loaded with the same power, and is flexed with less power by its self-weighted inertia. The rod tip which is bent by slower acceleration tracksstraighter than the fast taper. This may sound like a soft rod, but a soft rod does not have enough speed to accelerate the power when it repels.

The fast tapermakes the arc, because it does not have enough distance to be bent. This is one of the big reasons why many casters move their rods through too great an arc.

A solid rod is physically heavier than hollow rod, but it does not mean that it feels heavier. A solid rod does not need power to cast, and does everything that the rod has to do. It keeps enough power in the bending shaft and releases it when it should. This is why you feel the solid rod lighter is than the hollow rod while casting. You need to input less power, and it prevents your arm being tired during a day long fishing trip.

2. Heavier shaft hold the enough touch for initial speed

If you are a baseball pitcher, you will wind up to throw a fast ball. Because the wind up motion can hold the power to bring the initial velocity maximum when a ball is released. A quick/set up pitching motion cannot generate a high speed ball. The initial velocity is the key to throwing anything far. The Carbon fibers in Octagon’s shaft are all parallel to the lengthwise direction. This structure prevents a rod slow down when it needs the initial velocity and keeps the tip tracking. The max initial velocity depends on the modulus of elasticity when the rod recoils and releases it’s energy. A heavier shaft generates smooth acceleration, and the high modulus of elasticity brings the high initial velocity. These two factors combine to make the Octagon rod an outstanding performer.

The hammer throw, the javelin and the shot put are similar to when you cast a heavy weighted fly or bulky fly which has a large air resistance. You cannot do it quickly. Every athlete accumulates enough power while in preparation movement to maximize the initial velocity. The octagon performs the way those athletes do.

3.Thinner diameter reduces the air resistance

Air resistance is simply negative burden to any fly rod. The thinner rod r has lower air resistance. If a rod is flexed by inertia, the bend can store the power to propel the line and fly. But air resistance decreases the amount of energy stored in the rod. You must therefore increase the power in your stroke to overcome the increased air resistance. The thinner, the better is the rule of the fly rod. You can easily hear the difference by the sound of rod when you cast.

The diameter of the OCTAGON is approximately 70% of a hollow graphite rod. If you take a look at the flex curve of the Octagon Bonefish 8 weight rod, You will think it is a 4 weight trout rod. Less air resistance makes a rod tip travel faster, and this will contribute to a longer distance cast.

4. The rod blank no longer Ovals in cross section

The Octagon rod is not an easy to break rod. You even can step on the solid rod. A hollow rod gains the rigidity by increasing the diameter. But when it is bent, the round shape will be transformed into an oval. There is a myth in the fly rod world that oval shape accelerates the release of power, but this is not true in the real world. As a rod ovals it decreases the power as it loses the round shape. We all know a flattened hose does not have power to reshape. On the other hand, an Octagon rod will not be flattened easily, because it is solid. This solid structure contributes to the constant tenacity when you fight a big and powerful fish. Also, this strong structure allows rod designer to make a thinner tip rod. Thin and tenacious tip helps you create a narrow loop even in the short distance cast.


Round or polygonal, that is the question. In theory, you can cast straighter line with polygonal rods than round rod. Because each shaft’s face has it’s own two-dimensional power planewhich directs the line. The quad rod would be the best choice. The widest two-dimensional plane will maintain the power in line to bring the line straight forward. But the quad rod has the maximum air resistance which is totally negative for releasing the power with the least amount of power input.

The above theoryis the case when you move the fly rod identical 100% straight back and forth in the same plane. But you know, it is not likely to happen for most casters. Also the fish who has a fly in his mouth can pull your rod from 360 degree angle. Yes, the fly rod needs to handle unexpected power from any unexpected direction. The round shape rod is not the best rod shape to cast in the straight line, but is good at handling the twisted power.

The octagonal shape has both good features of polygonal and round rod, it can handle the unexpected power from any direction like the round shape rod. But unlike the round shape rod, the octagonal rod still has the two-dimensional power plane when you cast.


Octa ferrule

Have you ever had a hard time when you pull off the rod shaft after a long day fishing? Have you ever thrown a rod tip off while casting? Have you ever seen your rod’s guides misaligned while casting?

All of these annoying experiences are eliminated once you have an Octagon rod.

During the construction of the Octagon, the male and female ferrules are made separately. This construction gives us what we call multipoint contact method. By cutting male and female ferrule precisely, you can increase the point of contact surfaces of the ferrules. The precision multi point contact areas create friction, which is not easily loosened during casting.

Here is the way we make the perfect ferrule.

1. Cut the shaft of male octagonal section end

2. Wrap it with a carbon Filament

3. Make a hole for the female section

4. Insert 2 to 3 to bond together

5. Pull off 2 leaving carbon filament wrapping in the hole

6. Then you can get the perfect matching male and female ferrule in octagonal shape.

Unlike cylindrical contact, this large area contact method will keep male and female aligned perfectly together.

Ferrule flex or torsion is the origin of ferrule loosening. But our method reduces the influence of the torsion while allowing the ferrule to flex during the cast. The combination of Octagonal shape and large area contact method makes the octa ferrule the best ferrule ever made in fly rod history.

You no longer have to worry about ferrules coming loose during fishing.

Making a ferrule

Octa Grip

Have you ever wondered why a tennis racket handle is not a round shape? How about badminton’s? They are octagonal because flat surfaces deliver more power than round surface. It is notas slippery as the round shape grip and it helps maintain the plane of the casting action. All players sweat, but still they are playing on ground, not in the water. Why do we fly fishermen/women use round shape grip? We are playing in the water, and wet more than any other sports other than swimming!

We don’t know the exact reason nobody has challenged the shape of the fly grip. Now we are proposing the octagonal grip which we believe is the ideal shape for the fly fishing rod.

Infinity Guide (βTiN)

We chose an alloy of pure Titanium called β-TiN as the material of the guides for all of our Octagon rods. The color is similar to the brass, but the weight far lighter. We have to eliminate the excess weight of the guides to maximize the rod power. β-Titan is the material has the following characteristics.

1. Super Elasticity

2. Light, but yet very strong

3. Anti-rust

4. Low modulus of elasticity ratio

5. Soft, but yet surprisingly restorable

Unlike a stainless steel guide, β-Titan will never rust because of salt water. To make the surface smoother, the guides are all intruded. This treatment is applied not only on the surface, but also even into the material. So, the durability is greatly increased.

The shape of our guide is quite unique. Not Snake, not One-foot, but Closed Snake Guide, which we invented. Our snake guide has two feet for wrapping. This process brings additional weight to the rods. Nobody complained it, because it’s a standard for a long time. Closed Snake Guide still has two feet, but their feet are fold reverse, so we can wrap it like single foot. Not like a normal Snake Guide which extends two long legs towards both direction, Closed Snake Guide can reduce the unexpected stiffness from the shaft.

Need better photo replacing this/


Have you ever dreamed that you could make your own design for rod action? Now your dream can come true! It has been a black box you never could open, but we can open the door for you. Using no mandrel releases us from the inflexibility of mass production. Because by inputting the taper data to the Vertical Crawler, we can make any taper rod design. We have our standard taper we recommend for most fly fishers, but you still can request some additional adjustment such as “a bit stiffer in the butt”.

Other than the taper, you can select any of the rod component parts, and even color of the shaft.

Carbon material

We use 3 different kinds of carbon, which are 24ton, 30ton and 40ton TOREY carbon filaments. 24ton is standard, 30ton is mid-high, and 40ton is high Modulus of elasticity. We think 24ton is best for trout in the stream, 30ton is for the bigger trout like Steelhead, and 40ton is ideal for the saltwater. But you can choose whichever you think is best for your fishing style.

The biggest difference from the traditional hollowed graphite rod is the structure of the carbon layup. Traditional graphite rods use the prepreg carbon filament sheet (PrePreg) which has cross (lateral and longitude) fibers. We use a solid pultruded carbon cylinder in which the filaments only run in the longitudinal direction. This helps the rod tip tracking in the same plane and increases durability.


How many section?

Fishing is requires traveling, and we believe a 4 piece rod is the most flexible for those who travel. If you want to backpack the rod to a high mountain lake, we recommend a 6 piece rod. You can choose from 3 to 6 pieces.

Question from Vic - Does this mean you can’t build me a one piece 7 foot 3 weight solid octagonal rod?

Reel seat filler

Our reel seat is designed as an up-locking with sliding ring. You may be surprised to learn that we don’t use a screw lock reel seat even on the higher weight rods for Saltwater. A strong Titanium spring plate is hidden in the cork grip. When you set the reel foot into the upper hood under the grip, the opposite foot will extend over the reel seat, then slide the ring up to hold its tension. It’s much smoother than screw lock, and less likely to be become loose while fishing. Reel seat Insert of your choice

We have a vast selection of the woods, and you can choose from the wood list.

The Octagon rod’s reel seats are all coated with natural Cashew oil finish which is very durable yet very beautiful like Japanese Urushi paint.

Rod case

All rods come with cloth sock and original wood cap Aluminum tube.

You can order optional beautiful Cashew stained OCTACASE made with Tung woodthat can hold 3 rod tubes.


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